Poster
Abstract
Research summary supplied by the authors
Introduction • The tanning industry generates significant amounts of solid waste. • Post-tanning residues are difficult to recover and structured supply chains for their sustainable management are still lacking. • However, these wastes have strong potential for valorization within a circular economy framework. • In addition to leather wastes, agri-food wastes could be used to create innovative bio-based composite materials together with leather wastes. • Chitosan is a biological macromolecule with well-known antimicrobial and filming properties that is possible to exploit in leather manufacturing. Aim of the Study •Develop a sustainable method for the recovery of chrome-tanned leather shavings. •Apply acid hydrolysis using 1.5 M HCl to break down the protein matrix and obtain a soluble hydrolysate. •Formation of bio-based composite films intended for applications in the packaging sector, and alternative finishing to the synthetic polymer finishes currently used for leather. •Use zeolites to capture chromium in a stable form. •Obtain two main products: • a protein hydrolysate for use in the development of new biodegradable materials, • a chromium-zeolite powder allowing safe and efficient metal recovery. Initial hydrolysate Hydrolysate after 2 days of treatment Composite Film – front view Composite Film – section view ❖ The acid hydrolysis process proved to be highly effective, achieving an impressive yield of approximately 96%. ❖ The chromium capture treatment using zeolite reduced chromium content from 4.28% to 0.32% w/w. ❖ First samples of chitosan-hydrolysate composite films have been successfully prepared. These will be subjected to comprehensive chemical-physical and biodegradability characterizations.